New distances for a selected set of visual binaries with inconsistent dynamical masses

TL;DR

This paper examines 17 visual binary star systems with inconsistent mass estimates, proposing revised distances and orbital improvements to reconcile dynamical and luminosity-based mass calculations, primarily using dynamical parallaxes.

Contribution

It introduces a method for correcting parallax and orbital data for visual binaries to achieve consistent mass estimates, highlighting the importance of accurate distance measurements.

Findings

Nine binaries do not require orbit updates, only parallax adjustments.

Eight binaries need orbit improvements and possible parallax corrections.

Dynamical parallaxes help reconcile mass discrepancies in most cases.

Abstract

We have selected a set of 17 visual binaries that demonstrate great inconsistency between the systemic mass obtained through Kepler's Third Law as compared to that calculated through standard mass-luminosity and mass-spectrum relationships. A careful inspection of orbital data and parallaxes showed that the current orbits of nine binaries (WDS 00155-1608, WDS 00174+0853, WDS 05017+2050, WDS 06410+0954, WDS 16212-2536, WDS 17336-3706, WDS 19217-1557, WDS 20312+1116, and WDS 21118+5959) do not need to be improved, instead we recommend different parallax (distance) value for them. On the other hand, we considered that eight orbits (WDS 02366+1227, WDS 02434-6643, WDS 03244-1539, WDS 08507+1800, WDS 09128-6055, WDS 11532-1540, WDS 17375+2419, and WDS 22408-0333) had to be improved. Due to various reasons mentioned in this paper, their distances should most likely be corrected unless better orbital solutions and/or more precise parallaxes are reported. To obtain consistent mass values, the use of the dynamical parallax is still recommended for 5 out of the 8 improved orbits. For WDS 02434-6643, WDS 09128-6055, and WDS 11532-1540, the improvement itself yields reasonable mass sums while maintaining {\pi}_{Hip} within a 1-2{\sigma} margin. New distance estimates for 16 stars (mainly based on the obtained dynamical parallaxes) and individual comments for all objects are presented and discussed.